QB 51 

B31 
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A LECTURE 



:- S 



STUDIES IN ISTROiNY 



ELABORATED FOR GENERAL READERS. 



BY ARTHUR K/ BARTLETT. 



PUBLISHED BY THE AUTHOR. 



- i 



BATTLE CREEK, MICHIGAN. 



2£ 






Entered according to Act of Congress, in the year 1881. by 

ARTHUR K. BARTLETT, 

In the office of the Librarian of Congress at Washington. 

ALL RIGHTS RESERVED. 



STUDIES IN ASTRONOMY: 



— RKIXG — 



A Lecture on the Science, Elaborated with Numerous 
Additions for General Readers ; 



— EMBRACING ITS — 



P 



SUBLIMITY, HISTORY, PROGRESS, WONDERS, 
AND UTILITY, 

TOGETHER AVITH AN EXPLANATION OP 

SPECTRUM ANALYSIS, 

— AND A DISCOURSE ON — 

EVOLTJTIOISr XlfcT THE SKT, 

— INVOLVING THE — 

GROWTH AND DECAY OF WORLDS, 

Considered under the Light of Recent Scientific Researches. 



By ARTHUR K. BARTLETT, 



Astronomical Correspondent, Author of " The Science of Astronomy, 

Member of the American Association for the Advancement of 

Science, and Honorary Member of the Detroit 

Astronomical Society. 



"I shall straight conduct you to a hill-side, laborious indeed at the first 
ascent, but else so smooth, so green, so full of goodly prospect and melodious 
sounds on every side, that the harp of Orpheus was not more charming/' — 
Milton. 



SECOND EDITION. 
Revised, Re-written, and Enlarged. 






PUBLISHED BY THE AUTHOR. 

BATTLE CREEK, MICHIGAN. 



r 



/ fr£ 



s« 



TO MY ESTEEMED FRIEND, 

EDWARD M. BRIGHAM, 

In Recognition of His Enthusiastic Devotion to Science, 

and the Service He has Rendered to Education 

by His Journeys to South America, 

Resulting in Valuable Additions to the Natural 

History Collections of Michigan ; 

ALSO, 

as a Slight Acknowledgment of the 

Sympathy and Encouragement which I have Received from 

Him in My Scientific Studies, this Little Work is 

Most Gratefully and Affectionately 
DEDICATED. 



STUDIES IN ASTRONOMY. 



IHTBODUCTIOIT. 



••The heavens declare the glory of God; and the firmament 
showeth his handy work." Psalm xix, 1. 

LADIES AND GENTLEMEN: — 

The subject to which I have the pleasure of inviting 
your attention, is not only sublime, but one of stupen- 
dous magnitude. I intend to speak upon the general 
subject of astronomical science, — its sublimity, its his- 
tory, its progress, its wonders, its utility, and its en- 
couraging prospects for still further advancement in the 
distant future. If those present will but give me their 
earnest and unbroken attention while I introduce them 
in succession to the grand truths of astronomy, my task 
will be an exceedingly pleasant one. 

Astronomy is the most ancient of all sciences. The 
study of the stars is doubtless as old as man himself, 
and hence neither history nor tradition can inform us 
concerning the first discoveries in this sublime science. 
Astronomy is a study which has in all ages engaged 
the attention of the most learned men of the world. 
" Kings have descended from their thrones to render 
it homage, and have sometimes enriched it with their 
labors ; and humble shepherds, while watching their 
flocks by night, have beheld with rapture the blue 



4 STUDIES IN ASTRONOMY: 

vault of heaven, filled with its thousands of shining orbs, 
moving in silent grandeur, until the morning star an- 
nounced the approach of day." There is probably no 
human being who has for the first time turned his 
eyes toward the nocturnal sky, and beheld the moon 
"walking in brightness" among the hosts of stars and 
planetary orbs, marking off the hours, minutes, and sec- 
onds with an accuracy which no clock can ever rival, 
but must have been struck with awe and admiration at 
the splendid scene. 

Who has not looked up to the celestial vault on a 
calm, bright night, when "the immeasurable heavens 
break open to their highest, and all the stars shine," 
and said to himself, "What are these far-off lights?" 
Are they worlds similar to our own, or merely lights 
placed in the heavens by some invisible being, for the 
purpose of exciting our reverence and admiration? 
What are their distances from our earth, and are they 
governed by the same laws which characterize the 
world we inhabit? If these are worlds, can they be 
peopled by wise and intelligent creatures like ourselves? 
and does the Almighty rule over their destiny as he does 
over our own ? These, and similar questions, will natural- 
ly present themselves to all persons who allow their 
thoughts to soar among the star-depths. Even the 
little babe, in its weak and puny mind, looks up to the 
starry heavens, and perceives the beauties which they 
disclose, while filled with wonder and admiration. 
Many persons ask if these great celestial mysteries will 
ever be revealed to us, while others seem wholly un- 
concerned about them. A large number of these grand 
problems have already been solved, while others yet 
await the patient astronomer, whose keen eye, in gene- 



A LECTUKE ON THE SCIENCE. •> 

rations to come, shall be able to read the mysteries 
therein. The heavens are before us, inviting our study, 
and waiting to make known unto us the grandest reve- 
lations of science. 

Some enthusiastic writer has made the following 
truthful remark : " Perhaps there is no subject upon 
which the people are so profoundly misinformed as that 
of astronomy. Night after night they gaze up into the 
starry depths with as much intelligence as they would 
bestow upon a spangled wall-paper, — in fact, a degree 
less ; for in the one case, they know that they are span- 
gles, and in the other, they gaze on beautiful vacancy." 
The best reason known why so few persons care to study 
astronomy, is because the heavenly bodies can be so 
easily observed upon a clear sky. Prof. Henry Whitall, 
of New York, the inventor of the well-known " Mov- 
able Planisphere," so extensively used in the United 
States, makes the following true and interesting remark: 
" If there were but one spot on the earth where the gor- 
geous heavens were visible, and that a small place no 
larger than the State of New Jersey, there would not 
be a college in our land that would dare to graduate a 
pupil without that pupil being able to describe the won- 
ders within that little State ; and the education of no 
pupil would be considered complete until he had made 
a visit to see the beautiful stars which were visible on a 
clear evening within that little place." Because all can 
behold for themselves the starry heavens spread out to 
their view, is the principal reason why so few care to 
become acquainted with what all may see and know. 
The earth has the gift of captivating us so strongly, 
that we willingly forget the heavens for it. If some- 
times we allow ourselves to be exalted by the wonders 



6 STUDIES IN ASTRONOMY: 

of the skies, we quickly return to the things of earth, 
forgetting our grand celestial questions. 

"When morning sheds its gorgeous dye, 

Our hope, our heart, to earth is given ; 
But dark and lonely is the eye 

That turns not, at its eve, to heaven." 

The Sublimity of Astronomy, 

Nothing can be more grand, more awe-inspiring, than 
the contemplation of the starry heavens. The study of 
the stars is the most ennobling within the range of spec- 
ulative science. The mind that rises to the skies seems 
to soar above the littleness of earthly things, and in 
communing with the wonders of apparently silent but 
everlastingly rolling nature, one becomes purified, ele- 
vated, and in every way nearer to " the fear of God,' 
which "is the beginning of wisdom." Concerning 
the sublime and inspiring aspect of astronomy, Prof. 
Richard A. Proctor, the eminent English astronomer, 
very eloquently remarks, while referring to the beauties 
of the starry heavens: "The mind cannot but be 
strengthened and invigorated, it cannot but be purified 
and elevated, by the contemplation of a scene so full 
of magnificence, imperfect though the means be by 
which the wonders of the scene are made known to us. 
The information given by the telescope is indeed but 
by piecemeal, and as yet no adequate attempts have been 
made to bring the whole array of known facts as far as 
possible into one grand picture; but, seen as it is, only 
by parts, and (even so) only as through a veil and 
darkly, the scene presented to the astronomer is the 



A LECTURE ON THE SCIENCE. 7 

grandest and the most awe-inspiring which man can 
study." 

The starry heavens present an aspect which has been 
admired for its beauty by the poets in all ages. Thus 
wrote Byron, in his " Childe Harold's Pilgrimage": 

"Ye stars ! which are the poetry of heaven, 
If, in your bright leaves, we would read the fate 
Of men and empires, — 'tis to be forgiven, 
That in our aspirations to be great, 
Our destinies o'erleap their mortal state, 
And claim a kindred with you ; for ye are 
A beauty and a mystery, and create 
In us such love and reverence from afar, 
That fortune, fame, power, life, have named themselves 
a star." 

Every person should possess a certain knowledge 01 
the starry heavens. The late Thomas Carlyle, the em- 
inent author of England, regretted in his old age 
that he never learned the grand lessons of astronomy, 
and he said : " Why did not somebody teach me the 
beautiful constellations, and make me at home in the 
starry heavens, which are always overhead, and which 
I do n't half know to this day." These are the words 
of a distinguished scholar, and how many a man 
can say the same to-day ! What person would not ex- 
claim with the poet Virgil, 

" Give me the ways of wandering stars to know, 
The depths of heaven above, and earth below"? 

The Work of Astronomers, and their Longevity. 

Few persons can realize the great work which is being 
performed by astronomers in various parts of the world. 
Go to some large observatory at night, and if you are a 



8 STUDIES IN ASTRONOMY: 

favored visitor, you shall peep in at the solitary explo- 
rers of the universe, as they sit, in separate apartments, 
perched high upon curious ladders, or crouched in 
quiet corners. Their eyes are glued to apertures which 
are the windows looking out upon the infinite. When 
obscuring clouds do not sweep across their field of vis- 
ion, they will remain whole nights rooted to their 
places, pausing only to shift their machinery, or to jot 
a few memoranda, until the kindly light of morning 
drives their beloved stars from sight, and themselves to 
their repose. While the world sleeps around them, they 
pore, and strain, and study night after night, year after 
year. Proud to contribute their mite to the fund of the 
world's information, they will lay them down to their 
final rest, happier than emperors, if they have but dis- 
covered some few new planets, or more clearly demon- 
strated the character and movements of the older ones. 
Many of these "star-gazers" have bent over their books 
and machines until they have grown gray in their work, 
and extreme old age is now upon them. 

Most persons would naturally suppose that a study 
which requires such constant attention, often robbing 
the astronomer of his peaceful hours of slumber and re- 
pose, would somewhat abridge the period of life. But 
astronomers, as a class, are noted for their longevity, 
and generally outlive all other men. It is a remarkable 
fact, well worthy of notice, that distinguished astrono- 
mers most often die between the ages of seventy and 
eighty-five. Sir William Herschel, the greatest astron- 
omer of modern times, died at the advanced age of 
eighty-three ; and so did Lalande, who, it is said, often 
remained whole nights in his attic for the purpose of 
studying the stars and planets. The late Sir John 



A LECTURE ON THE SCIENCE. 9 

Herschel (son of Sir William) died at the age of seven- 
ty-nine j and Prof. Airy, the eminent Astronomer 
Royal of England, is still living at a "ripe old age." 
The late Prof. Olmsted, of Yale College, in his excel- 
lent work, " Letters on Astronomy," said: "I know 
not how to account for this fact, unless we suppose that 
the study of astronomy itself has something inherent 
in it, which sustains its votaries by a peculiar ali- 
ment." 

Every person who pursues this sublime study can read 
a noble lesson in the distant skies. But those who re- 
ceive their knowledge of astronomy merely second- 
handed, — turning aside from the -worry and excitement 
of a business life, to hear what a "star-gazer" has to 
say, — are unable to fully realize the grand truths which 
the heavens unfold to professional astronomers in their 
great observatories. Prof. Agassiz, the eminent old 
scientist, who has now gone to his rest, has made the 
following impressive remarks: "The glance at the 
moon, or at Jupiter's satellites, which the chance visi- 
tor at an observatory is allowed to take through the gi- 
gantic telescope, reveals to him nothing of the intense 
concentrated watching by which the observer wins his 
higher reward. The nightly vision of the astronomer, 
revealing myriad worlds in the vague, nebulous spaces 
of heaven, is not for him ; he must take the great re- 
sults of astronomy for granted, since no astronomer, 
capable of original research, has the time to prepare for 
the uninitiated the attendant circumstances essential to 
his more difficult investigations, or to train their eyes to 
see what he sees." 



10 STUDIES IN ASTRONOMY: 

A Brief History of the Science. 

Nothing can be more interesting in astronomical 
science than to trace its history and wonderfully rapid 
progress. For a long period, during the infancy of 
this science, comparatively little was known of the ce- 
lestial bodies excepting their apparent motions and 
aspects. Instead of investigating with care their true 
motions and relative distances and magnitudes, many 
of our ancestors looked up to the sky, either with a 
brute, unconscious gaze, or viewed the heavens as a 
book of fate, in which they might read their fortunes, 
and learn, from the signs of the zodiac, and the various 
aspects of the planets, the temperaments and destinies 
of men, and the fate of empires. Even to this day, and 
in our own civilized country, the foolish art of " cast- 
ing a horoscope," and prognosticating fortunes by the 
stars, is one of the principal uses to which the science 
of the heavens is applied. 

The subject of astronomy is so vast and inexhaustible 
that it cannot be dealt with in a single lecture ; and in 
tracing the history of this science, I shall speak only of 
those most important facts which will best enable my 
audience to understand its progress and glorious achieve- 
ments. Prof. O. M. Mitchell, the celebrated astrono- 
mer, who established at Cincinnati the first observa- 
tory of any importance in the United States, and died 
in the defense of his country, has thus pictured, in 
eloquent language, man's first view of the starry heav- 
ens : — 

"Often have I swept backward, in imagination, six 
thousand years, and stood beside our Great Ancestor, 
as he gazed for the first time upon the going down of 



A LECTURE ON THE SCIENCE. 11 

the sun. What strange sensations must have swept 
through his bewildered mind, as he watched the last de- 
parting ray of the sinking orb, unconscious whether he 
should ever behold its return. Wrapt in a maze of 
thought, strange and startling, his eye long lingers 
about the point at which the sun had slowly faded from 
his view. A mysterious darkness, hitherto unexperi- 
enced, creeps over the face of nature. The beautiful 
scenes of earth, which through the swift hours of the 
first wonderful day of his existence had so charmed his 
senses, are slowly fading, one by one, from his dimmed 
vision. A gloom deeper than that which covers earth, 
steals across the mind of earth's solitary inhabitant. 
He raises his inquiring gaze toward heaven, and lo ! a 
silver crescent of light, clear and beautiful, hanging in 
the western sky, meets his astonished eye. The young 
moon charms his untutored vision, and leads him up- 
ward to her bright attendants, which are now stealing 
one by one from out the deep blue sky. The solitary 
gazer bows, and wonders, and adores. The hours glide 
by — the silver moon is gone — the stars are rising — 
slowly ascending the heights of heaven, and solemnly 
sweeping downward in the stillness of the night. The 
first grand revolution to mortal vision is nearly com- 
pleted. A faint streak of light is seen in the east — it 
brightens — the stars fade — the planets are extinguished 
— the eye is fixed in mute astonishment on the growing 
splendor, until the first rays of the returning sun dart 
their radiance on the young earth and its solitary inhab- 
itant. To him ' the evening and the morning were the 
first day.'" 



12 STUDIES IN ASTRONOMY: 

Ancient Astronomers and Their Theories. 

What a grand, imaginary description of man's first 
view of the starry heavens ! But, let us now consider 
what the human mind has accomplished during its long 
and patient struggle of six thousand years. Generation 
after generation has passed away, age after age has 
swept silently by, but each has swelled, by its contribu- 
tion, the stream of astronomical discovery. There is 
reason to believe that astronomy was studied by the an- 
tediluvians. It is certain that this science was culti- 
vated in Western and Central Asia, within two or three 
centuries after the flood. Noah, probably, communi- 
cated some knowledge on the subject to his descendants. 
There was an ancient tradition that the patriarch 
Abraham was somewhat acquainted with this science; 
and it is evident that Job, a little later, was not igno- 
rant of it, as may be seen from the Scriptures. History 
also informs us that the people of India understood 
astronomy, to some extent, eighteen hundred years be- 
fore the Christian era. But the first careful observers 
of the heavens were the ancient shepherds, who, as 
they watched their flocks at night beneath the celestial 
canopy, naturally became interested in the orbs with 
which it was studded, and gave names to those that 
were most conspicuous. They knew, however, only 
such isolated facts as were apparent to the eye. It was 
reserved for later years to trace visible effects to their 
causes, and to advance theories; and not until the 
improved instruments of comparatively recent times 
extended the field of human vision almost beyond be- 
lief, was it possible to penetrate the mysteries of the 
heavens to their depths. 



A LECTURE ON THE SCIENCE. 13 

In this enlightened age of the world, the ideas of the 
ancients respecting the starry heavens appear absurd and 
almost incredible, and we can hardly understand how 
they could have been seriously entertained. The Chal- 
deans and Egyptians were the first to make any material 
progress in astronomy, and they were particularly dis- 
tinguished for the accuracy and extent of their observa- 
tions. The former, by continued observation, discov- 
ered that the eclipses of the moon recur in the same 
order, at intervals of eighteen years, and were thus able 
to predict them with considerable accuracy ; the latter 
investigated the motions of the planets, and established 
a sacred year of 365^ days. The Chinese, also, paid 
great attention to this science in very early times, and 
these people boast much of their astronomical discov- 
eries. They have the earliest record of a solar eclipse, 
which occurred about 220 years after the flood. More 
than 2300 years before the Christian era (according to 
their own records), a tribunal was established for the 
prosecution of astronomical studies, and particularly 
for the prediction of eclipses ; and it is reported that 
one of their kings actually put to death his two chief 
astronomers because they had failed to calculate an ap- 
proaching eclipse of the sun. 

Advancement in Knowledge.— The "Copernicau 
System. 5 ' 

From Egypt, the cradle of learning, science, and art, 
the Greeks obtained their first knowledge of astronomy. 
Thales, about 600 years before Christ, taught that the 
world was round, and that the moon shone by reflected 
light, borrowed from the sun. " He introduced the 
division of the earth's surface into zones," and first 



14 STUDIES IN ASTRONOMY : 

propounded the theory of the obliquity of the ecliptic. 
He also established the first school of astronomy in 
Greece. Anaximander, one of his pupils, conceived 
the bold idea that the planets are inhabited. Pythago- 
ras, a little later, first conceived a system of the uni- 
verse, which was in many respects correct, and he is 
said to have advanced the idea that the planets revolved 
round the sun. But he advanced no proof in support 
of his views, and they were soon well-nigh forgotten. 
Among other celebrated Greek astronomers were Era- 
tosthenes, who devised an accurate method for measur- 
ing the circumference of the earth \ and Hipparchus 
(known as the "Patriarch of Astronomy," and the 
"Newton of Antiquity "), who calculated the length of 
the tropical or solar year to within six minutes, discov- 
ered the precession of the equinoxes, and made the first 
catalogue of all the conspicuous stars visible above his 
horizon, — 1081 in number. He also recorded the re- 
spective latitudes and longitudes of 1022 stars, together 
with their apparent magnitudes, and has been justly 
regarded as the most eminent of the ancient astrono- 
mers. Ptolemy, an eminent Egyptian astronomer, who 
flourished in the second century after Christ, rejected 
the theory of Pythagoras respecting the Solar System, 
and advanced one of his own, which soon met with 
general acceptance. He taught that the earth was the 
center of a system of eight immense hollow spheres of 
crystal, placed one within another • that the moon was 
in the nearest sphere ; Mercury in the next; Venus in 
the third ; the sun in the fourth ; Mars, Jupiter, and 
Saturn in the fifth, sixth, and seventh respectively ; and 
that the eighth belonged to the stars, which, though 
most distant, were still visible through the transparent 



A LECTURE ON THE SCIENCE. 15 

crystal. The revolution of this cumbrous system 
around the earth from east to west, once in twenty-four 
hours, he thought would account for the succession of 
day and night, and the various phenomena of the heav- 
ens. , 

During the Dark Ages of the world, when every man 
was his own astronomer, this science was cultivated 
chiefly by the Arabians, who made no advance as re- 
gards theory, but were diligent observers, and devised 
some improvements in instruments and methods of 
calculation. Even after the termination of this period, 
comparatively little progress was made until the time of 
Copernicus, a German priest, over 350 years ago. He 
ventured to reject the system of Ptolemy, which was 
still taught in all the institutions of learning in Europe, 
and reviving the teachings of Pythagoras, set forth 
what is called the " Copernican System," now very 
generally received as true by astronomers, although at 
first bitterly denounced as visionary and even irreligious. 
" For over forty years, this illustrious astronomer car- 
ried on his observations in the upper part of a humble, 
dilapidated farm-house, through the roof of which he 
had an unobstructed view of the sky. The work con- 
taining his theory was finally published just in time to 
be laid upon his death-bed." The three fundamental 
points of the "Copernican System" are: First, that 
the earth is round ; second, that it turns upon its axis 
from west to east ; and third, that the earth and 
all the other planets revolve around the sun as a cen- 
ter. 



1G STUDIES FN ASTRONOMY : 

Some Important Discoveries.— Kepler, Galileo, 
and Newton. 

After Copernicus came Tycho Brahe, a celebrated 
Danish astronomer, who propounded a theory in modi- 
fication of the " Copernican System," and believed 
with Ptolemy that all the celestial bodies revolved 
about the earth as a center, in circular orbits, from east 
to west, every twenty four hours. This astronomer had 
a pupil named Kepler, who rejected the theory of his 
master; and advocating that of Copernicus, finally 
enunciated three grand truths of planetary motion, 
known as " Kepler's Laws," — the result of eighteen 
years' assiduous and toilsome observation. A full ex- 
planation of these great laws, in order to render them 
comprehensible, would require a series of diagrams, and 
more time than could be given to the subject within the 
limits of a single lecture ; but I will state them to my 
audience, in the order of their discovery, as follows: — 

First, — All the planets, including the earth, 

REVOLVE IN ELLIPTICAL ORBITS, WITH THE SUN SITU- 
ATED AT ONE OF THE FOCI. 

Second, — The radius vector of every planet, — 

THAT IS, AN IMAGINARY LINE JOINING A PLANET WITH 
THE SUN DESCRIBES EQUAL AREAS IN EQUAL TIMES. 

Third, — -The squares of the periods of revolu- 
tion OF THE PLANETS AROUND THE SUN, ARE PROPOR- 
TIONAL TO THE CUBES OF THEIR MEAN DISTANCES FROM 

THE SUN. 

These three laws are the foundation of our astronom- 
ical knowledge, and form one of the most glorious 
achievements of the human mind. When Kepler fully 



A LECTURE ON THE SCIENCE. 17 

realized the vast importance of his discoveries, he was 
completely overwhelmed with emotion, and at last, in 
the wild excitement of his glorious triumph, the great 
philosopher of the heavens exclaimed : " Nothing 
holds me ; I will indulge my sacred fury ! If you 
forgive me, I rejoice ; if you are angry, I can bear it. 
The die is cast. The book is written, to be read either 
now or by posterity, I care not which. It may well 
wait a century for a reader, since God has waited six 
thousand years for an observer ! ' ' 

Contemporary with Kepler was the celebrated Italian 
astronomer, Galileo, who improved and first made prac- 
tical use of the telescope, with which he was enabled to 
make many brilliant discoveries, all tending to support 
the theory of Copernicus. He directed his telescope 
toward Jupiter, and discovered four satellites accom- 
panying this planet in its revolution around the sun — a 
beautiful " Copernican System " in miniature, hung up 
in the heavens for all to see and examine for themselves. 
Who has not heard of 

" The starry Galileo with his woes "? 

The discoveries of this great astronomer met with the 
most bitter opposition. Because he believed that the 
earth revolved around the sun, and turned upon its 
axis, he was obliged to appear at Rome, and answer be- 
fore the Inquisition for his seemingly absurd ideas. It 
was there that Galileo, a feeble old man of seventy 
years, kneeled down before the Cardinals, and with his 
hand upon the Bible, declared that he " abjured, de- 
tested, and abhorred the heresy of the earth's motion 
around the sun." But, as the old, gray-headed philos- 
opher tottered out from the presence of the tribunal, it 



18 STUDIES IN ASTRONOMY: 

is said that he muttered to himself, "E pur si muove" — 
and yet the earth does move. This is now an evident 
fact, and so the whole world believes to-day. 

The day on which Galileo died was memorable for 
the birth of Sir Isaac Newton, who discovered the 
grand law of " Universal Gravitation " which explained 
the planetary motions. Other astronomers had pre- 
pared the way, and it was reserved for Newton to 
make this important discovery, which gave a new im- 
petus to astronomical science ; or, in the words of the 
poet: — 

" Nature and Nature's laws lay hid in night : 
God said, 'Let Newton be,' and all was light." 

Perplexing Movements of the Planets. 

After all the brilliant discoveries had been made in 
relation to the Solar System, nothing was more difficult 
for the ancient astronomers to explain than the appar- 
ent motions of the planetary bodies. If the position 
of any planet among the stars be carefully observed 
from night to night, it will be noticed that it does not 
always move in one direction through the heavens, but 
will sometimes be observed to direct its motion toward 
the east for a certain period of time, and then suddenly 
halt in its course, remain stationary for a while, and 
begin to move in retrograde order toward the west, con- 
tinuing in that direction until it will again come to a 
very sudden stop, and then, after remaining without 
the least apparent motion for another short interval, 
commence to retrace its course toward the east as before. 
Such are the apparent movements of these far-off worlds 
as observed from the earth. All the planets revolve 
around the sun in one direction, — -from west to east. 



A LECTURE ON THE SCIENCE. 19 

Why, then, do they sometimes appear to move over the 
sky, from west to east, then halt, remain stationary, 
and after a short interval, direct their course toward 
the west, contrary to the direction in which they at first 
appeared to move? This is a question which, for many 
generations, puzzled and perplexed the ancient readers 
of the sky. They knew very well (as taught by old Co- 
pernicus) that the planets moved about the sun as a 
center, and also in the same direction ; but the most in- 
telligent and best informed of the ancient astronomers 
could not explain the peculiar and complicated move- 
ments of the planets as observed from our earth. Their 
knowledge of the heavens slowly increased, and it was 
finally surmised that the peculiar and unexplained mo- 
tions which characterized the planetary bodies were ow- 
ing to the fact that we did not observe them from the 
center of their orbits, but from the earth, which was 
also constantly shifting its position in space, and caus- 
ing them to move with apparent irregularity through the 
sky. These were their views, and they have since been 
demonstrated to be correct. If, then, we could observe 
the planets from their center of motion, — the sun, — we 
should perceive these bodies moving around us at vari- 
ous distances, but all in the same direction, — from west 
to east. 

Modern Astronomy. — Discovery of the Planet 
Uranus. 

Having thus briefly traced the history and progress of 
ancient astronomy, let us now consider some of the mod- 
ern discoveries in this science, which clearly illustrate 
the ability of man to grapple with the grand problems 
of the skies. There is nothing more encouraging in 



20 STUDIES IN ASTRONOMY: 

the history of astronomical science than the remarkable 
success which has rewarded the observations of modern 
astronomers. From the earliest ages, the mighty orbit 
of the planet Saturn was supposed to form the boundary 
of the Solar System. The slow and majestic motion of 
this planet, its great period and distance, and the won- 
derful magnificence of its rings and moons, seemed to 
render it a fitting object to guard the frontiers of the 
mighty system with which it was associated. But it is 
a well-known fact, as the result of Newton's grand dis- 
covery, that all the planets exert an attraction upon each 
other, and produce certain orbital disturbances, which 
are called perturbations. Near the close of the eight- 
eenth century, when the planetary motions had been 
observed with great care, and a comparatively accurate 
knowledge of their perturbations had been acquired, 
certain unexplained motions of Saturn gave rise to the 
belief that another planet revolved around the sun in a 
vast orbit far beyond that of Saturn. On the 13th of 
March, 1 781, while Sir William Herschel was engaged 
in examining some stars in the constellation Gemini, 
his attention was attracted to a small star of remarkable 
appearance, which fortunately happened to pass into the 
field of his great telescope. He examined the strange 
star with higher magnifying powers, when it appeared 
greatly increased in dimensions, and exhibited a sensi- 
ble disk. After watching it for several evenings, Her- 
schel noticed that its position changed among the stars, 
and not even dreaming that the body was a planet, he 
announced to the world that he had discovered a new 
and remarkable comet. But it required only a short 
time to convince the astronomical world that the body 
in question was a member of the Solar System. It is 



A LECTURE ON THE SCIENCE. 21 

now known as the planet Uranus, represented in the il- 
lustration* before you as the seventh in order of dis- 
tance from the solar orb. This planet is situated at a 
mean distance of 1771 millions of miles from the sun, 
and requires eighty-four of our years to complete its 
vast circuit around that luminary. Here is a brilliant 
astronomical discovery, which may be regarded as the 
result of a merely accidental observation. 

Another Brilliant Discovery.— The Planet 
Neptune. 

We will now consider a still more remarkable discov- 
ery, which is regarded as one of the most glorious 
achievements of the human mind. For many years 
after the discovery of Uranus, the movements of this 
planet were such as to baffle the most accurate calcula- 
tions. While the planet Saturn came around to its 
place true to the minute and second, even after its jour- 
ney of nearly thirty years, it was found that the planet 
Uranus did not strictly conform to the path assigned to 
it. It was finally suggested by several astronomers that 
another planet revolved around the sun outside the or- 
bit of Uranus, which disturbed the movements of this 
planet, and produced its perturbations. The disturbing 
influences of Jupiter and Saturn, the only planets which 
could affect the motions of Uranus appreciably, had 
been taken into account ; and the masses of these plan- 

*In delivering this lecture, the subject was illustrated with 
large oil paintings ; and although the original references to them 
are retained, it has been thought unnecessary, in preparing the 
lecture for publication, to introduce diagrams, as some alterations 
have been made which will doubtless render the explanations 
clear without them. 



22 STUDIES IN ASTRONOMY: 

ets had been far too satisfactorily ascertained to leave 
any doubt as to the effects which they could produce on 
Uranus. Sir William Herschel had carefully studied 
the movements of Uranus, and so firmly did he believe 
in the existence of another planet, more remote from 
the sun, that he remarked: "We see it as Columbus 
saw America from the shores of Spain. Its movements 
have been felt trembling along the far-reaching line of 
our analysis, with a certainty not far inferior to occular 
demonstration." 

It is one of the most difficult problems presented to 
an astronomer "to determine the motions of a planet 
when all the circumstances which can affect that motion 
are known." The great problem presented to the as- 
tronomer was this : " Given the disturbances produced 
by the attraction of an unknown planet, to find its or- 
bit, and its place in the orbit-" Only two astronomers 
in the world were bold enough to attempt the solution 
of this problem. These two were Leverrier, of France, 
who died recently at the age of sixty-eight, and Adams, 
of England, both young mathematicians, who, each un- 
known to the other, undertook the difficult task of find- 
ing the place of the supposed planet. Leverrier was 
not quite unknown to science in his own country, al- 
though comparatively at the beginning of his astronom- 
ical career. Adams was a scientific student of unusual 
ability, and was preparing to receive his degree at 
Cambridge University. None but those who understand 
the difficulties involved in a mathematical question of 
this kind, can fully realize the magnitude of the prob- 
lem which was presented to these young men for 
solution. Adams first completed his calculations, after 
nearly two years of toilsome labor, and in October, 



A LECTURE ON THE SCIENCE. 23 

1845, ne submitted them to Prof. Airy, the Astronomer 
Royal of England. A few months later, Leverrier pre- 
sented his calculations to the Academy of Science in 
Paris, and announced the figure of the orbit of the 
supposed planet, its distance from the sun, its period of 
revolution, and even the mass of matter which it con- 
tains. On the 23d of September, 1846, Leverrier 
wrote to Prof. Galle, of Berlin, for assistance in search- 
ing for the imaginary planet, and requested him to di- 
rect his great telescope to a certain point in the heav- 
ens. Prof. Galle, on that same evening, did as requested, 
and after a few moments' observation, he discovered a 
star of the eighth magnitude, which he knew to be a 
stranger in that region of the heavens, as it was not 
laid down on the most accurate maps. This proved to be 
the predicted planet, which was discovered within less 
than two diameters of the moon's disk from the spot 
indicated by Leverrier, or what would appear to be 
about one foot, as seen upon the sky. 

It is but justice to young Adams to add, that after 
the discovery of this planet by Prof. Galle, he perfected 
his own calculations, and arrived at results almost iden- 
tical with those of the French mathematician, although 
he was entirely unknown to him, and had pursued an 
independent train of reasoning. The brilliant discov- 
ery of this planet was the result of pure mathematical 
calculations, and fully demonstrates the power of 
the human intellect to comprehend the great laws of 
nature. Far sweeping in the depths of space, unseen 
by mortal eyes, this new world pursued its solemn jour- 
ney, reflecting back the light of the solar orb, steadily 
obedient to the grand law of Universal Gravitation, 
which held the old planets true to their changing orbits. 



24 STUDIES IN ASTRONOMY : 

This planet has received the name of Neptune. The 
news of its discovery spread in every direction, and 
filled the world with astonishment and admiration. 
Neptune is the most remote planet from the sun at 
present known to astronomers, — the far-off sentinel of 
the planetary system. It requires 165 of our years to 
complete a single revolution around the sun, at the 
enormous distance of 2775 millions of miles. Such is 
a brief history of one of the grandest achievements of 
the human mind, and the world will always be glad to 
honor the names of Leverrier and Adams, who, by their 
remarkable knowledge of the mathematics of the skies, 
won for themselves an enviable fame, and a position in 
the foremost ranks of modern astronomers. 

Spectrum Analysis Explained.— Important 
Researches. 

We now come to the most wonderful discovery in 
modern astronomical science since the planet Neptune 
was added to the solar system. The ancient astrono- 
mers never dreamed that the constitution of the stars 
and planets would ever be ascertained. But even this 
astounding success has been achieved, and we are now 
permitted to speak — and speak with confidence — of 
" Celestial Chemistry," as made known to us by a new 
science called " Spectrum Analysis." By "spectrum 
analysis ' ' is meant the chemical analysis of substances 
by means of a wonderful instrument known as the 
" Spectroscope." If abeam of white sunlight is allowed 
to enter a darkened room through a small aperture in 
the window shutter, and then passed through a triangu- 
lar prism of glass, we find that it is separated into the 
seven colors of the rainbow. These, collectively, pro- 



A LECTURE ON THE SCIENCE. 25 

(luce what is called the "Solar Spectrum." This may 
be easily formed by any person by procuring a triangu- 
lar piece of glass, and allowing the sunlight to pass 
through it, when a most beautiful spectrum can be seen; 
or a somewhat similar effect may be produced by simply 
looking through one side of the glass toward a strong 
light ; and the beautiful combination of colors which 
we observe is termed a "Spectrum," whatever the 
source may be from which the light is derived. What 
person has not amused himself by looking through the 
triangular glasses of a parlor chandelier, and observing 
the brilliant colors of the rainbow? This amusement, 
on a much larger and grander scale, has worked won- 
ders in modern science, and enabled the astronomer 
to solve some of the most interesting problems of the 
skies. 

The discovery of the solar spectrum was made by 
Sir Isaac Newton \ but the beautiful coloring is only a 
small part of it. In 1802, the solar spectrum was found 
by Dr. Wollaston to be crossed, at right angles, by a 
large number of dark lines. These have been called 
" Fraunhofer's Lines," in honor of Prof. Fraunhofer, 
who mapped the plainest of them with great accuracy. 
In 1859, Prof. Kirchhoff, a distinguished German phi- 
losopher, discovered the real character of these lines, 
and their important significance respecting the physical 
constitution of the sun, stars, and planets. I now invite 
your attention to this illustration of the solar spectrum, 
which, I hope, will render clear the manner in which 
astronomers are able to ascertain the various substances 
existing in the celestial bodies. Here is represented a 
beam of white sunlight coming into a darkened room 
through a small slit in the window-shutter, and, upon 



26 STUDIES IN ASTRONOMY : 

passing through a triangular glass prism, the beam is 
separated and spread out into a beautiful fan -shaped 
band of light, exhibiting all the colors of the rainbow. 
If a screen be suitably placed to receive the dispersed 
sunlight, we will find a beautiful rainbow-tinted streak, 
composed of seven colors, arranged in the following or- 
der, commencing at the top, and naming them down- 
ward in regular succession : Violet, indigo, blue, green, 
yellow, orange, red. This brilliant band of colors 
forms what is called the " solar spectrum." I have al- 
ready stated that the " Fraunhofer Lines" observed in 
the solar spectrum are dark. When the light from an 
artificial source is passed through a prism, and its spec- 
trum is examined by the spectroscope, no dark lines are 
visible, but instead of these, there will be seen lines 
of various bright and beautiful colors. The color of 
these lines, and their place in the spectrum, depends 
upon the substance from which the light proceeds. For 
example : If the metal sodium be burned in a hot gas 
flame, two bright yellow lines will always appear in the 
yellow part of the spectrum, while the metal potas- 
sium in the flame will always give two lines; one, of 
a brilliant crimson color in the red end of the spec- 
trum \ the other, a beautiful blue line far up in the 
violet end. It was also discovered that each substance 
burning invariably gave forth its own peculiar system of 
lines. 

Upon these few facts rests the whole science of "spec- 
trum analysis." Now, what is very remarkable, it was 
found that the position of these bright lines coincided 
with those of the dark lines in the solar spectrum. 
Here is a diagram of the spectrum given by the metal 
sodium in a vaporous condition^ This is found to be 



A LECTURE ON THE SCIENCE. 27 

the quality of a spectrum given by a gaseous body. 
You will here observe the position of the two bright 
lines referred to. In the solar spectrum are found two 
dark lines which occupy precisely the same position as 
those of sodium. Various other substances giving 
bright lines, are also represented by dark lines in the 
solar spectrum. Now, what intelligence do these facts 
convey to the astronomer? It has been found that the 
dark lines of the solar spectrum indicate vapors cooler 
than the sun's mass, which intercept a portion of its 
light, and that the lines are produced by the absorption 
of light while passing through the sun's atmosphere. 
Thus arise the dark lines; and the astronomer only 
wants to know the exact position of these lines to ascer- 
tain what elements exist in the sun. The spectrum of 
a star also exhibits most of the dark lines found in the 
solar spectrum, which indicate that the stars are suns 
like our own. Most of the nebulae and comets give a 
spectrum of bright lines, thus proving beyond a doubt that 
they are of a gaseous nature. By means of the spec- 
troscope, astronomers have learned that all the celestial 
bodies have nearly one identical constitution, and possess 
many elements which exist and even sustain life upon 
our own world. 

"All are but parts of one stupendous whole, 
^"hose body nature is, and God the soul." 

Future Revelations of the Spectroscope.— Its 
Important Applications in Modern Science. 

It is impossible to foresee what may yet be accom- 
plished by the spectroscope, — the most wonderful and 
important instrument of modern science, — for, as an 
English astronomer has recently remarked, " Matters 



28 STUDIES IN ASTRONOMY: 

of pure conjecture to-day may become entirely settled by 
the spectroscope to-morrow." It affords the most del- 
icate and trustworthy means at present known for ana- 
lyzing chemical substances, and has already revealed 
many new elements and substances before unknown to 
the chemist. So delicate is this instrument as a chem- 
ical test, that it will easily detect the -25ooooo tn P art °f 
a grain of sodium ; and when all other means of analy- 
sis fail, the chemist then appeals to the spectroscope, 
with the most accurate and astonishing results. One of 
the most recent and important applications of the spec- 
troscope to the science of astronomy, is its employment 
as a means of determining what stars are approaching 
and receding from the earth, which is regarded as one 
of the greatest and most interesting achievements of 
modern times in the department of stellar astronomy. 
The spectroscope divests the sunbeam of its mysteries, 
after traveling over ninety millions of miles, and reveals 
to us the chemical constitution of the planets, comets, 
and even the distant stars. To quote the eloquent lan- 
guage of Dr. Warren, author of a recent work on as- 
tronomy : " In the near future we shall have the brill- 
iant and diversely-colored flowers of the sky as well 
classified into orders and species as are the flowers of the 
earth." 

We thus see the vast importance of spectrum analysis. 
By a few mysterious, and at first unattractive lines, as- 
tronomers have been able to make the most wonderful 
discoveries of modern science. And silently these lines 
will continue to speak to us, and more and more intelli- 
gently and eloquently as we rise higher in the intellect- 
ual scale, and become better fitted to hold conversation 
with them. It is from our knowledge of spectrum 



A LECTURE ON THE SCIENCE. 29 

analysis that astronomy will reach us, and from the rev- 
elations of the spectroscope that the future progress of 
this science will advance. 

The Grand Results of Astronomical Research. 

Such have been the glorious achievements of modern 
astronomy. We have traced the wonderful progress of 
the human mind during its long and toilsome struggle 
of more than sixty centuries, One barrier after another 
has given way to the steady march of astronomical sci- 
ence, until the human mind, majestic in its strength, 
has mounted step by step up the rocky height of its 
self-built pyramid, from whose lofty summit it looks out 
upon the grandeur of God's universe ! The grand re- 
sults of human investigation cannot fail to fill the mind 
with astonishment, and to demonstrate the truthful pas- 
sage of Scripture, that man has been made but a little 
lower than the angels. These brilliant achievements 
of astronomy have not resulted from the labors of any 
o?ie astronomer. No one astronomer has ever grasped 
enough to accomplish much by himself. But each as- 
tronomer has done his own little part, all the more 
thoroughly because it has been so small, and the aggre- 
gate result is a grand one. What tribute can we now 
pay to the memory of that unknown mortal who first 
resolved to read and comprehend the starry heavens? 
To quote the eloquent language of Prof. Mitchell : 
"On some lofty peak he stood, in the stillness of the 
midnight hour, with the listening stars as witnesses of 
his vows, and there, conscious of his high destiny, and 
of that of his race, resolves to commence the work of 
ages. ' Here,' he exclaims, •' is my watch-tower, and 
yonder bright orbs are henceforth my solitary compan- 



30 STUDIES IN ASTRONOMY: 

ions. Night after night, year after year, will I watch 
and wait, ponder and reflect, until some ray shall pierce 
the deep gloom which now wraps the world.' Thus re- 
solved the unknown founder of the science of the stars. 
His name and his country are lost forever. What mat- 
ters this, since his works, his discoveries, have endured 
for centuries, and will endure as long as the moon shall 
continue to fill her silver horn, and the planets to roll 
and shine ? " 

The Increasing Popularity of Astronomy, 
and Its Remarkable Accuracy. 

Astronomy is now becoming more popular than ever 
before. This is by no means a matter of surprise, as no 
other science is doing so much to benefit the world at 
large. If any proof were needed that the people of 
this country are beginning to appreciate the value of 
astronomical knowledge, no greater could be found than 
the interest with which the beautiful comet of 1874 was 
observed, and the remarkable success which attended 
the popular lectures of Prof. Proctor, the eminent En- 
glish astronomer, during each of his three visits to 
America. Night after night, this great scientist stood 
before crowded audiences in our largest cities, expound- 
ing the grand truths of modern astronomy, and rejoic- 
ing in his noble work. Astronomy is now the most 
perfect of the sciences, and hence astronomers are en- 
abled to predict results with absolute precision thou- 
sands of years before they occur. They announce that 
on such a year, month, day, hour, minute, and second, 
a celestial body will occupy a certain position in the 
heavens. At the time indicated, we point our telescopes 
to the place, and at the exact instant, true* beyond the 



A LECTURE ON THE SCIENCE. 31 

accuracy of any time-piece, the orb sweeps into view. 
Here permit me to exhort you in the beautiful language 
of the poet : — 

"Come forth, O man, yon azure round survey, 
And view those lamps which yield eternal day, 
Bring forth thy glasses, clear thy wondering eyes, 
Millions beyond the former millions, rise : 
Look further : millions more blaze from yonder skies." 

It is not to be expected that all persons who pursue 
this charming study will eventually become celebrated 
astronomers; but it should be the duty of every votary 
in astronomical science, to record all known phenom- 
ena, to arrange and classify the facts, to discover, if 
possible, the relations of the laws which he observes ; 
and if he cannot discover at once the sublime marvels 
of the heavens, he can classify all observations for 
other astronomers who succeed him, in order that they 
may themselves work with better hope of success. The 
small number of votaries in astronomical science should 
be increased. Every other profession is now full, and 
that of astronomy alone needs more enthusiastic work- 
ers. There are always certain persons who seem to be 
prejudiced against astronomy. They will not only shun 
this exalting science themselves, but even persuade oth- 
ers not to study it. Would that such persons could only 
appreciate Tennyson's beautiful lines : — 

"Let knowledge grow from more to more, 
But more of reverence in us dwell ; 
That mind and soul, according well, 
May make one music as before, 
But vaster." 



32 STUDIES IN ASTRONOMY : 

Inspiring Aspect of the Sky in Autumn 
and Winter. 

I can think of nothing which seems better calculated 
to lead men to choose astronomy as a favorite subject 
of study, and to inspire one with an emotional love for 
this science, than the magnificent scenery of our noc- 
turnal sky at this season of the year. During the au- 
tumnal and winter months, the starry heavens put on 
their grandest and most attractive appearance. The 
brightest stars in our firmament — fifteen being of the 
first magnitude — are at present visible upon the evening 
sky, and great constellations, meandering over a large 
extent of the heavens, continue above our horizon 
throughout the entire night, presenting a scene beauti- 
ful beyond description. 

The evening sky in autumn and winter is glorious 
with its constellations. Toward the south, at an early 
hour in the evening, during the months of December and 
January, may be seen the beautiful constellations of 
Taurus and Orion. Overhead shine Auriga, Perseus, 
and Andromeda, with Aquila, Delphinus, Lyra, and 
Cygnus further west ; and in the east are Lepus, Cetus, 
and Canis Major. These constellations alone include 
twelve stars of the first magnitude, all of which are 
above the horizon, and may be seen on every clear 
evening during the winter. 

" Thus monstrous forms, o'er heaven's nocturnal arch 
Seen by the sage, in pomp celestial march ; 
See Aries there his glittering bow unfold, 
And raging Taurus toss his horns of gold ; 
With bended bow the sullen Archer lowers, 
And there Aquarius comes with all his showers : 
Lions and Centaurs, Gorgons. Hydras rise, 
And gods and heroes blaze along the skies." 



A LECTURE ON THE SCIENCE. 33 

Compared with the grand appearance of our evening 
sky at this season of the year, the most resplendent ter- 
restrial scenes sink into nothingness, and appear un- 
worthy of being set in competition with the glories of 
the starry heavens. 

The Practical Importance of Astronomy, 

Do you now ask what is the practical utility of astro- 
nomical science ? Many of the benefits derived from 
astronomical observations are perhaps too apparent in 
our day to need much explanation before an intelligent 
audience. Independently of the sublimity of its ob- 
jects, and the pleasure arising from their contemplation, 
astronomy is a study of vast utility, in consequence of 
its connection with the terrestrial arts and sciences, 
many of which are indebted to the observations and the 
principles of this science for that degree of perfection 
to which they have attained. Prof. Steele makes the 
following impressive remarks, concerning the value of 
the stars in practical life : " The stars are the landmarks 
of the universe. They seem to be placed in the heav- 
ens by the Creator, not alone to elevate our thoughts, 
and expand our conceptions of the Infinite and Eter- 
nal, but to afford us, amid the constant fluctuations of 
our own earth, something unchangeable and abiding. 
Every landmark about us is constantly changing, but 
over all shine the ' eternal stars, ' each with its place so 
accurately marked that to the geographer and astrono- 
mer no deception is possible. To the mariner, the 
heavens become a dial-plate, the figures on its face set 
with glittering stars, along which the moon travels as a 
shining hand that marks off the hours with an accuracy 
that no clock can ever rival. ... In all the in- 



34 STUDIES IN ASTRONOMY: 

tricacies of surveying, the stars afford the only immuta- 
ble guide. Our clocks vainly strive to keep time with 
the celestial host. Thus, by a wise provision of Provi- 
dence, even in the most common affairs of life, are we 
compelled to look for guidance, from the shifting ob- 
jects of earth, up to the heavens above." — Steele" s As- 
tronomy, p. 233. 

The great practical purpose of astronomy to the world 
consists in enabling us safely to navigate the ocean. 
Astronomy has proved of indescribable benefit to the 
navigator : for, without some knowledge of this science, 
- he never could have traced his course over the great 
ocean to any far-distant land. It is of vast importance 
for the mariner to know on what part of the globe he is 
situated at any time in the mighty ocean ; also to un- 
derstand many other particulars which can be deter- 
mined only by astronomical observations of the utmost 
accuracy. The following extracts from the writings of 
three different authors beautifully illustrate the utility 
of this science in its application to navigation, as well 
as to other benefits which we derive from it ; and the 
first quotation describes one of the most important op- 
erations in practical astronomy : — 

" Place an astronomer on board a ship; blindfold 
him ; carry him by any route to any ocean on the globe, 
whether under the tropics, or in one of the frigid zones j 
land him on the wildest rock that can be found j remove 
his bandage, and give him a chronometer regulated to 
Greenwich or Washington time, a transit instrument 
with the proper appliances, and the necessary books and 
tables^ and in a single clear night he can tell his posi- 
tion within one hundred yards, by his observations of 
the stars." — Newcomb' s Popular Astronomy, p. 103. 



A LECTURE OX THE SCIENCE. 95 

u A ship that leaves our shores for a voyage around 
the world, takes with it a book called the ' Nautical 
Almanac,' prepared three or four years in advance by 
government astronomers. In this book, the places the 
sun, moon, stars, and planets will occupy at certain 
stated hours for each day, are given, and this informa- 
tion is all that sailors and travelers require to find their 
way across pathless seas or unknown lands. A predic- 
tion of the ' Nautical Almanac ' is received with as 
much confidence as if it were a fact contained in a book 
of history. On the trackless ocean, this book is the 
mariner's trusted friend and counsellor; daily and 
nightly its revelations bring safety and happiness to 
ships in all parts of the world. It is something more 
than a mere book. It is an ever-present manifestation 
of the order and harmony of the great universe of 
God." — Steele' 's Fourteen Weeks in Astro?io?ny ■, p. 308. 

"But we need not go on board ship, or into new 
countries, to find out the practical uses of astronomy. 
It is astronomy that teaches us to measure the flow of 
time, — the length of the day and the year; without as- 
tronomy to regulate them, our clocks and watches would 
be quite useless to us. It is astronomy that divides the 
year into seasons for us, and teaches us the times of the 
rising and setting of the moon, which illuminates our 
night. It is to astronomy, also, that we must appeal 
when we would inquire into the early history of our 
earth, or wish to map its surface." — Lockyefs Ele- 
ments of Astronomy, p. 15. 

Astronomy has also been of great utility to the sci- 
ence of geography ; for without a certain knowledge of 
the heavens, the true figure of our globe would never 
have been ascertained. The manner in which Colum- 



36 STUDIES IN ASTEONOMY: 

bus discovered the rotundity of the earth was by ob- 
serving its shadow during an eclipse of the moon. Be- 
fore that time, most persons believed that the earth was 
a smooth -and boundless plain, and that if its limits 
could be reached, they would fall into what was termed 
the " abyss of tartarus." But to-day the mighty ocean 
is traversed by steam and sail, and commerce is carried 
on in all parts of our civilized world. 

Even religion has been greatly benefited by astronomy, 
without a knowledge of which, missionaries would never 
have been carried across the ocean to teach the heathen 
and other uncivilized people of the existence of a God. 
If any persons wish to be thoroughly convinced that a 
Divine Power does rule supreme, they need only direct 
their eyes upward to the nocturnal sky ; for there is no 
better evidence of the existence of an Almighty Crea- 
tor, than the precise structure and management of our 
starry heavens. 

" View the amazing canopy ! 

The wide, the wonderful expanse ! • 

Let each bold atheist agree 

That God is there, unknown to chance." 

Truly, "An undevout astronomer is mad." The 
study of astronomy is direct intercourse with the 
Master Mind, and the earnest devotee of this science 
is prepared to "look through nature, up to nature's 
God." 

The Wonders of Astronomy.— Interesting Facts 
Regarding the Sun. 

Let us now consider some of the wonders of astro- 
nomical science. To those who have given but little 
attention to the study of astronomy, many of the great 



A LECTURE ON THE SCIENCE. 37 

facts which I am about to state, will doubtless seem as- 
tonishing and almost incredible. I will first invite 
your attention to the wonders of the sun, — the great 
fountain of life, light, and heat of our planetary system. 
The diameter of this great orb is 860,000 miles. You 
will perhaps be able to understand these figures better 
by comparison. In this illustration, the larger circle 
is intended to represent the shell of the sun. Now, if 
we imagine our earth placed here at the center of the 
sun, there would be enough space for the moon to re- 
volve in its regular orbit, represented by the smaller 
circle, at a distance of 240,000 miles, within the 
sun's circumference, besides leaving 200,000 miles 
stretching in every direction beyond ! The volume 
of the sun is 1,245,000 times that of our earth; that is, 
it would require 1,245,000 earths to make a globe equal 
in size to that of the sun. The mass of the sun is 674 
times that of all the other members of the solar system 
taken together. Recent calculations from observations 
of the last transit of Venus, which occurred in the year 
1874, show that the distance of the sun from the earth 
is about 92,000,000 miles. Light, which travels with 
the almost inconceivable velocity of 186,000 miles 
every second, requires more than eight minutes to reach 
us from the sun. If an express train could start 
from the sun, and travel night and day, at the rate 
of thirty miles an hour, it would require 340 years to 
reach our earth. Prof. Proctor says that if an infant 
were born, having an arm 92,000,000 miles long, so as to 
reach the sun ; and if, in the cradle, he were to lift out 
his arm and touch this luminary, that infant might 
grow to the threescore years and ten allotted to man, 
but he never would be conscious of the fact that the tip 



38 STUDIES IN ASTRONOMY : 

of his finger was burned. He would have to live 135 
years before that would be experienced. Perhaps it 
would be well for some infant to try this experiment 
just once, to see if the professor is correct ! 

The distance of the sun seems enormous to us ; yet, 
it is used by astronomers as a unit for expressing celestial 
distances I We receive enough heat from the sun annu- 
ally to melt a solid layer of ice 38 yards in thickness, 
extending over the whole earth. Sir John Herschel 
says, that if a solid cylinder of ice, 45 miles in diam- 
eter, and 200,000 miles long, were plunged, end first, 
into the sun, it would melt in a single second of time; 
and yet, it is interesting for us to know that the heat 
is 300,000 times more intense upon the surface of the 
sun than it is upon our earth, and also that we receive 

onl y the 23000^0006 P art of the total energy— light, 
heat, and chemical activity — radiated by the sun in 
every direction throughout space. This glowing orb, 
which appears so small to us, is the scene of tremendous 
activity. Here on earth we sometimes witness fearful 
tornadoes ; but there are atmospheric disturbances tak- 
ing place on the sun, compared with which those of our 
earth are utterly insignificant. Is it a wonder, then, 
that persons once worshiped the sun, that great lumi- 
nary whose rays bring so many blessings to us, and 
without which all life would cease to exist ? 

" Great source of day ! best image here below 
Of thy Creator, ever pouring wide, 
From world to world, the vital ocean round ; 
On nature write, with every beam, His praise." 



A LECTURE ON THE SCIENCE. 39 

Wonders of the Star-Depths.— Motions of the 

Stars. 

If these facts relating to the sun seem astonishing to 
you. the wonders of the star-depths will seem still more 
so. To ordinary vision, the stars appear at rest in our 
heavens ; nor can the astronomer himself recognize any 
signs of motion, except by patient and long-continued 
observation, extending, in some instances, over a period 
of many years, and even centuries, when succeeding as- 
tronomers complete the work which their predecessors 
had begun. But every star in the firmament is on its 
journey, and moving through space with wonderful ve- 
locity. Absolute rest is unknown throughout the ma- 
terial universe. If we look up to the sky on a calm, 
bright night, when the stars shine forth in all their 
glory, we are usually impressed with the feeling that a 
solemn stillness reigns throughout those infinite depths. 
This is the idea suggested to the imagination of the 
poet ; nor is any other view apt to present itself to those 
who are unfamiliar with the teachings of modern' as- 
tronomy. But those amazing star-depths above us, 
which appear so steadfast and unchangeable from year 
to year, are astir with life, energy, and activity, and 
there is a wonderful process of change taking place all 
around us. Our own earth is moving with us constantly 
and rapidly in its orbit, eighteen miles per second, with 
nearly every beat of the pulse ! This is our velocity as 
reported by the astronomers, and while we sleep seven 
hours, the world on which we dwell moves 470,000 miles ! 
It is believed by many astronomers that the sun, with its 
family of planets and comets, is moving through space 
toward the constellation Hercules ! In my explanation 



40 STUDIES IN ASTRONOMY: 

of Spectrum Analysis, I stated that the spectroscope 
has shown what stars are approaching and receding from 
the earth. Among the stars found to be approaching 
the earth, is Arcturus, — mentioned in the Bible, and the 
brightest star in the northern hemisphere, — which 
is moving with a velocity of fifty-five miles every sec- 
ond. Sirius, the "Dog Star," and "King of Suns/' 
so glorious on winter evenings, and the brightest star in 
the heavens, is receding from us at the rate of twenty- 
five miles a second ; and yet, even with these enormous 
velocities, the passage of a million years will make no 
perceptible difference in the appearance of these two 
stars, so great are the distances which separate them 
from our earth ! 

The greatest velocity that has been recognized among 
the stars, is found in the motion of .a star known as 1830 
Groombridge, — or the " Runaway Star," as it is some- 
times called, — which is believed to be rushing through 
space at the rate of two hundred miles per second. 
This star appears to be moving in a perfectly straight 
path through the sky, as do all of those stars which are 
found to have a "proper motion" independently of 
each other, and it may be visiting our stellar system for 
the first time \ but whence it came, or whither it is go- 
ing, no one can tell, and it is a great enigma to astron- 
omers. Its wonderful velocity cannot be explained, 
and is greater than could be caused by the influence of 
all the known bodies in the universe ; and on the other 
hand, the combined attraction of all the orbs of heaven 
cannot stop this star in its solitary flight through the 
sky, until it has rushed on to the extreme limits beyond 
which the greatest telescopes have never penetrated. 
Then, possibly, but not until then, will this remarkable 



\ LECTURE ON THE ^< rENCE. 41 

star yield to the overpowering attraction of the millions 
of suns which belong to our universe; but what will 
become of it in future centuries, when its enormous 
velocity has been so far reduced that its forces of resist- 
ance no longer hold supremacy, and finally become 
expended, it is beyond the power of man to conceive, 
unless we imagine that it will be compelled, by the at- 
traction of another universe, to move in a new path, 
and continue on forever in its irresistible career. 

It has been mathematically demonstrated, that a body 
approaching the center of our system, from an infinite 
distance, cannot move with a greater velocity than 
twenty-five miles a second, if influenced by the attrac- 
tion of the masses in our universe alone : but here we 
are considering a star moving with eight times that ve- 
locity, and still, notwithstanding the fact that it has the 
greatest motion known among the stars, it would require 
185.000 years for this star to complete an entire circuit 
around the heavens ! 

Our entire universe of stars is constantly undergoing 
vast changes, which will be perceptible to those who 
inhabit the earth in future centuries. The configura- 
tions of our starry heavens will eventually be greatly 
changed from their present appearance. Orion will 
then no longer hold supremacy over the constellations. 
The well-known ''Big Dipper" will sometime, in the 
distant future, assume a different appearance from that 
now presented to our view, and must finally cease to at- 
tract the attention of thousands who to-day admire its 
beautv in our northern skies. 



42 STTTDTES TN ASTRONOMY : 

Evolution in the Sky.— The Growth and Decay 
of Worlds. 

There are wonderful processes of evolution taking 
place in the star- depths. The work of creation has not 
yet ceased, — as many persons of bigoted religious propen- 
sities believe, who accept the Bible as the only reliable 
authority, — but is still going on before our eyes, and the 
heavens afford to our view the process of world-making 
in all its various stages. It is a remarkable fact that 
the idea of the gradual transmutation of nebulae into 
stars was suggested to astronomers long before the doc- 
trine of evolution had become fully established. 

These paintings, to which I now invite your atten- 
tion, are intended to illustrate the process of world- 
making in different stages of advancement. Here is a 
representation of the large, faint, and diffused class of 
nebulae, irregular in outline, and of a cloudy aspect, in 
which the process of central condensation into stars 
seems to have hardly begun. Nebulae of this descrip- 
tion have been seen scattered over the heavens in great 
numbers, and the spectroscope shows that they are 
composed entirely of gaseous matter. 

These nebulae are stellar systems in their incipient 
stages of creation, and exhibit to us the crude material 
out of which worlds are made, — " world stuff" as it 
has been appropriately called by astronomers. This is 
the highly-attenuated nebulous substance out of which 
Laplace supposed our Solar System to have been evolved 
by gradual condensation, and upon which he founded 
his famous " Nebular Hypothesis/' assigning the gene- 
sis of the sun and planet-family to a process of growth 
and development. Thus, when we observe these faint 



A LECTURE ON TTTK SCIENCE. 43 

nebulae, we can sec in the heavens the same kind of 
material under the very form once presented by our 
Solar System, according to the nebular hypothesis. 

In this picture is shown the smaller but brighter class 
of nebulae, which have so far condensed that the central 
parts will soon begin to form stars. Here is another 
kind in which stars have actually begun to form ; and 
finally you see represented a star-cluster, in which the 
condensation is all completed. 

This picture shows the appearance of the great spiral 
or "whirlpool nebula," in the constellation Canes 
Venatici, or the Hunting Dogs, one of the most won- 
derful objects to be seen in the heavens. It has two 
centers of condensation, around which the stars appear 
to be forming ; and in this nebula we see indications 
of gigantic forces in operation, the nature of which is 
entirely unknown to astronomers. The number of spi- 
ral nebulae known is not large, compared with the other 
forms which have been observed, but the one repre- 
sented here is the largest and most interesting object of 
its class. To all appearances, it is rotating with great 
rapidity, as indicated by its spiral convolutions when 
seen through a large telescope, although no actual mo- 
tion of the object can be observed. This nebula pre- 
sents the very appearance which the nebular hypoth- 
esis assumes in accounting for the origin of our Solar 
System, and its spiral aspect would lead us to believe 
that it is a rotating mass, out of which a sun and system 
of planets will ultimately be evolved. 

The next picture represents the great gaseous nebula 
in Orion, as it appears through a telescope in the High 
School building, at Battle Creek, Michigan. It was 
painted from a drawing which I made of this nebula, 



44 RTUDTES IN ASTRONOMY: 

with the aid of this instrument, over five years ago, and 
is a fair representation of the wonderful object as seen 
with a high magnifying power. Here you will ob- 
serve four stars forming a beautiful " trapezium," where 
only one star can be seen with the naked eye; and here 
are three stars, arranged in nearly a straight line, which 
show how nebulous matter is observed to cling around 
certain stars, just as if the substance composing the neb- 
ula was drawn in from surrounding space in order to 
form these stars ; and in such cases, we see a convinc- 
ing demonstration that the work of creation has not 
ceased, but on the other hand we are able to recognize 
before our eyes the great processes of evolution which 
are still taking place all around us in the starry heavens. 

An almost infinite variety of nebulous forms may be 
observed through the telescope ; and although we can- 
not see any one particular nebula pass through all the 
stages of its progress, yet we can observe different neb- 
ulae in each stage of advancement, and thus recognize 
the full process of their growth and development. 

We cannot conceive how vast must have been the 
periods of time required for the formation of these won- 
derful nebulae, — periods compared with which, even 
the Archaean, Paleozoic, Mesozoic, and Cenozoic times 
of geology, immense as they are known to have been, 
— shrink into insignificance, and seem but as moments 
in the flight of eternity ! God does not do things in a 
hurry, but takes time, and works on slowly through the 
ages. He does not create a universe in six days, and then 
stop to rest, but, as a recent writer has well remarked, 
" He takes a thousand years to lift his hand off; " and 
it is by slowness that His most stupendous operations 
are accomplished. Surprising as it may seem to you, 



A LECTURE ON THE SCIENCE. 45 

it is nevertheless a fact that more nebulae are now 
known and catalogued than there are stars visible to the 
naked eye in the whole heavens. About 6,200 of these 
objects are at present known to astronomers, and over 
two -thirds of this number were discovered by the two 
Herschels, — father and son — the elder Herschel having 
alone discovered and described 2,508 nebulae and star- 
clusters during his brilliant career as an observer of the 
heavens. 

Our own Solar System once formed part of a large 
nebula — according to the ingenious speculations of La- 
place — and has been slowly condensed into its present 
proportions. Many of these far off nebulae are believed 
to be distant universes, and the telescope reveals them 
in all conceivable forms, and degrees of condensation. 
A recent work on astronomy, by Rev. H. W. Warren, 
contains the following passage regarding evolution in 
the heavens: " Suns are of all ages. Infinite variety 
fills the sky. It is as preposterous to expect that every 
system or world should have analagous circumstances to 
ours at the present time, as to insist that every member 
of a family should be of the same age, and in the same 
state of development. There are worlds that have not 
yet reached the conditions of habitability by men, and 
worlds that have passed these conditions long since. 
But let them go on. There are enough left, and an in- 
finite number in course of preparation. Some are fine 
'and lasting enough to be eternal mansions in the sky." 

Recreations in Astronomy, p. 214. Prof. Proctor 

says that " Nebulae may be looked upon as flowers in a 
garden, in different stages, — one springing from the 
earth, another in full bloom, and another in seed-time." 



STUDIES IN ASTRONOMY: 



Cosmogony.— The Future of Our Earth. 

The cosmogony of our universe, involving the growth 
and decay of worlds and systems, is of all subjects the 
most profound, sublime, and interesting to contemplate. 
Not only are new worlds being ushered into existence, 
but old ones are disappearing from the heavens. While 
new stars have at times suddenly blazed forth in the 
heavens with incomparable splendor, where none were 
visible before, there are many instances on record of 
stars having been destroyed by fire, and vanishing en- 
tirely from our view. The history of astronomy affords 
no records of phenomena more startling and remarkable 
than that of stellar conflagrations ; and when we con- 
sider what has befallen other worlds, we are naturally 
led to inquire whether our own may not eventually 
share the same fate. The Bible informs us that " the 
heavens shall pass away with a great noise, and the ele- 
ments shall melt with fervent heat ; the earth also, 
and the works that are therein, shall be burned up. ' ' 
Destruction by fire will doubtless be the ultimate fate of 
our world. It is prophesied by the Scriptures, and 
inscribed in the heavens above us. Science and Reve- 
lation harmonize on this important question, if they do 
not concerning any other ; and both agree in pointing 
forward to a time when an ordeal by fire will be the 
final end of our world. 

Here we are, in the presence of the Infinite, stand- 
ing, as it were, upon the verge of eternity, and not 
knowing "what a day may bring forth." To quote 
the eloquent language of Prof. Proctor: "There is 
infinite darkness enshrouding and overshadowing us. 



A LECTURE ON THE SCIENCE. 47 

A few links of the mighty chains which bind the uni- 
verse together have been traced, and others may some 
day be perceived, but we know that the chains are end- 
less. We stand in the presence of many infinities, be- 
fore which the soul trembles, perplexed and dismayed 
by infinity of mystery." But still, amid the destruc- 
tion of systems, and the wreck of worlds, we have the 
comforting assurance of the Scriptures that " while the 
earth remaineth, seed-time and harvest, and cold and 
heat, and summer and winter, and day and night shall 
not cease." 

We cannot tell in what way, or from what source, 
our earth will be destroyed by fire ; but we have good 
reason to believe that long before such a catastrophe 
can occur, the earth must first grow cold, and finally 
arrive at that state of refrigeration through which the 
moon is now passing. In fact, we see in the case of the 
moon, a picture of what our earth will be at some future 
time; and I sometimes think that our satellite was 
placed by the Creator the nearest celestial body to our 
earth, not only to sway the tides of the ocean, and il- 
luminate our nights, but also that we may read from its 
face what the future destiny of our world will be. Prof. 
Proctor says: " The moon must have cooled off six 
times faster than the earth, and is in the same condi- 
tion that the earth will be in 2,500,000,000 years hence. 
The moon gives us a good idea, probably, of the way 
our earth will look 2,500,000,000 years from now." 
Then, after the life and energies of our world have be- 
come exhausted, it will doubtless arrive at that desolate 
condition so eloquently prophesied and described in 
Byron's "Darkness," when the stars shall wander, 
"darkling in the eternal space, rayless and pathless," 



48 STUDIES IN ASTRONOMY: 

and the " icy earth M shall swing " blind and blacken- 
ing in the moonless air," — 

" Seasonless, herbless, treeless, manless, lifeless; 
A lump of death, a chaos of hard clay." 

The moon is regarded by astronomers as a dead, 
cold, and worn-out world, destitute of life, and in an 
advanced stage of physical development. Our world 
must eventually, through its gradual loss of heat, reach 
the same desolate condition ; and, as Prof. Winchell, 
of the Michigan University, has truly said, in his 
" Sketches of Creation " : " Every year and every day 
witnesses the dissipation of terrestrial warmth. While 
we ponder the great fact, the world is growing cold be- 
neath our feet. The current of events is carrying us 
inevitably to a state of .total refrigeration." In refer- 
ring to the future of our earth, and the present condi- 
tion of the moon, he also says: " These thoughts sum- 
mon into our immediate presence the measureless past 
and the measureless future of our material history. 
They seem almost to open vistas through the eternities, 
and to endow the human intellect with an existence 
and a vision exempt from the limitations of the finite, 
and lift it up towards a sublime apprehension of that 
Supreme Intelligence whose dwelling-place is eternity. " 
— Geology of the Stars, p. 31. 

The Finite Duration of Worlds.— Conclusions 
of Eminent Astronomers. 

It is now generally believed by the leading astronomers 
and other scientists of the world, that our earth has not 
existed from eternity in its present condition, and will 
not remain forever in the same state of development, 



A LECTURE ON THE SCIENCE. 49 

but that it is undergoing processes of evolution, which 
lead us to the conclusion that it will have its day, and 
at some future time cease to exist as a world. At least, 
this is what modern science teaches us to believe ; and 
if the earth had a beginning, it is reasonable to expect 
that it will sometime have an end. This idea is enter- 
tained by the most eminent of our modern writers on 
science; and Prof. Simon Newcomb, of the United 
States Naval Observatory at Washington, in his admi- 
rable work on astronomy, recently published, says: — 
" All modern science seems to point to the finite dura- 
tion of our system in its present form, and to carry us 
back to the time when neither sun nor planet existed, 
save as a mass of glowing gas. How far back that was, 
it cannot tell us with certainty ; it can only say that 
the period is counted by millions of years, but probably 
not by hundreds of millions. It also points forward to 
the time when the sun and stars shall fade away, and na- 
ture shall be enshrouded in darkness and death, unless 
some power now unseen shall uphold or restore her. ' ' 
— Popular Astro7iomy, p. 89. 

Another recent work, written by two American as- 
tronomers who rank among the most eminent authors 
of the world, contains the following statement, regard- 
ing the conclusions to be drawn from the nebular hy- 
pothesis : — " The widest generalization associated with 
it is that, so far as we can see, the universe is not self- 
sustaining, but is a kind of organism which, like all 
other organisms we know of, must come to an end in 
consequence of those very laws of action which keep it 
going. It must have had a beginning within a certain 
number of years which we cannot yet calculate with 
certainty, but which cannot much exceed 20,000,000, 



50 STUDIES IN ASTRONOMY : 

and it must end in a chaos of cold, dead globes at a 
calculable time in the future, when the sun and stars 
shall have radiated away all their heat, unless it is re- 
created by the action of forces of which we at present 
know nothing." — Newcomb and Holderi s Astronomy, 
p. soi. 

We know that the earth, stars, and planets are "wind- 
ing up their career ; ' ' but how long a time must elapse 
before our world loses all of its heat, becomes refriger- 
ated as the moon is at present, and finally passes through 
its fiery ordeal, until it is "burned up" and destroyed, 
our present knowledge will not enable us to determine, 
and we must ever remain in ignorance concerning this 
question, of such momentous import to us all. " Can'st 
thou by searching find out God? Can'st thou find out 
the Almighty to perfection ? " No, the ways of the Al- 
mighty are "past finding out," and we can never hope 
to fathom the purposes of that great Being, 

"Who sees with equal eye, as God of all, 

A hero perish, or a sparrow fall ; 

Atoms or systems into ruin hurled, 

And now a bubble burst, and now a world." 

The Mysteries of the Universe.— Notable 
Changes among the Stars. 

The mysteries of the universe surround us on every 
side, and the further we penetrate with our knowledge, 
the more do we see beyond, in the contemplation of 
which even the imagination is bewildered, until the 
mind grows weary in its efforts to grapple with the un- 
solved problems of the universe ; and at last, the words 
of the Psalmist compel us to acknowledge their truthful- 



A LECTURE ON THE SCIENCE. 51 

ness and significance: " O Lord, how manifold arc thy 
works! in wisdom hast thou made them all." Con- 
stant changes are taking place in the star-depths, and 
the wonderful processes of evolution are in perpetual 
operation. 

One of the most notable examples of the changes 
taking place in our firmament, is to be found in the mo- 
tions of the seven bright stars forming the " Big Dip- 
per," in the constellation Ursa Major. Here is a dia- 
gram showing the stars of the "Big Dipper " in their 
present position. These little arrows indicate the di- 
rection in which the stars are moving, and these dotted 
lines show the outline of the "Big Dipper," with which 
you are all familiar. You will observe that five of these 
stars are moving in the same direction, which shows 
that they are in some manner associated with each 
other. By a careful study of the motions of all these 
stars, Prof. Flammarion, a distinguished French astron- 
omer, has been able to represent the outlines formed by 
them at various times in the past, and those which they 
will form in the distant future. One hundred thousand 
years ago, according to his calculations, the stars form- 
ing the " Big Dipper " were arranged in the outline of 
a large and irregular-shaped cross, the appearance of 
which is represented in the middle diagram ; and one 
hundred thousand years hence, they will assume the out- 
line of an elongated and inverted " Dipper," stretch- 
ing over a large extent of the sky, the appearance of 
which is represented in this lower diagram. 

The notions hitherto entertained as to the stars and 
the heavens, are destined to undergo a complete revolu- 
tion. There are no " fixed stars." Each one of those 
distant suns, flaming in infinitude, is swept along in a 



52 STUDIES IN ASTRONOMY: 

stupendous movement, which the imagination can hardly 
conceive ; and your humble servant ventures to predict, 
that before many years have elapsed, there will be rec- 
ognized among the stars a variety of constitution, and 
complexity of arrangements, strikingly contrasted with 
the general uniformity of structure, at present taught in 
most of our text-books on astronomy. 

"Roll on, ye stars ; exult in youthful prime ; 
Mark with bright curves the printless steps of Time ; 
Near and more near your beamy cars approach, 
And lessening orbs on lessening orbs encroach. 
Flowers of the sky, ye, too, to age must yield, 
Frail as your silken sisters of the field. 
Star after star from heaven's high arch shall rush, 
Suns sink on suns, and systems systems crush, 
Headlong, extinct, to one dark center fall, 
And death, and night, and chaos mingle all ; 
Till o'er the wreck, emerging from the storm, 
Immortal nature lifts her changeful form, 
Mounts from her funeral pyre, on wings of flame, 
And soars and shines, another and the same." 

A Stupendous Problem. — Distances of the 
Stars. 

The problem which astronomers have to solve in as- 
certaining the distances of the stars, is one of the most 
stupendous difficulty. Of all the thousands of stars 
which have been studied, astronomers know the dis- 
tances of about twenty, and these are known only ap- 
proximately, being the supposed distances within which 
it is believed they cannot be, but beyond which they 
must be, although the exact limits cannot at present be 
ascertained, owing to the immense distances which sep- 
arate them from our earth. The nearest star is so re- 



A LECTURE ON THE SCIENCE. 53 

mote that its light requires 3^ years to reach us, while 
the light of the pole-star is 50 years in reachingus from 
that distant orb ; so that if the light of this star was 
extinguished to-day, 50 years would have to elapse be- 
fore we should be aware of the fact ! 

The mathematical principles involved in determining 
the distance of a star, are essentially the same as those 
employed by the surveyor when he wishes to measure 
the width of a stream which he cannot cross ) only, 
with the astronomer the problem is rendered much 
more complicated from the fact that he is unable to 
procure a base-line of the sufficient length to meet his 
requirements; and even the diameter of the earth's 
orbit is not great enough to use in measuring the dis- 
tances of the stars, with very few exceptions. To learn 
the distances of the stars, it is first necessary to de- 
termine what is known as a star's parallax, or its angle 
of direction when viewed from two opposite points in 
the earth's orbit, and this is what renders the problem 
so extremely difficult ; for nearly every star in the heavens 
that has been examined for the purpose of learning its 
distance, has failed to show any parallax whatever, and 
in the few instances where a parallax has been recog- 
nized, the angle is found to be exceedingly small. No 
star in the heavens has a parallax equal to one second, 
but all thus far determined are below even this small 
angle. 

The star which gives the greatest parallax of any, and 
is believed to be the nearest to our earth, is Alpha 
Centauri, a first-magnitude star in the southern heavens, 
and never visible in our latitude. But even this star's 
parallax is only y 9 -^ of a second, which corresponds to 
a distance of 221,000 times the sun's distance from our 



54 STUDIES IN ASTRONOMY : 

earth, or over twenty trillions of miles ! And this, re- 
member, is the nearest star at present known to astron- 
omers. The earth's orbit, seen from this star, would 
appear the same as a circle six-tenths of an inch in di- 
ameter, seen at the distance of one mile ; and the radius 
of that orbit, — or the distance which separates our earth 
from the sun, — wouid be hidden by a fine thread, or 
spider's web, -^ of an inch in diameter, held 650 feet 
from the eye ! "That is to say, a line 184,000,000 
miles long, looked at broadside, would shrink into a 
mere point. If our sun were removed to that distance, 
it would shine with a light only equal to that of the 
north star, while its parallax would be but the y^- of a 
second." 

There are stars so remote that their light cannot reach 
us in less than 10,000 years. To traverse the Milky 
Way, of which our own solar system forms a part, light 
requires 15,000 years ; and to reach us from some of the 
distant nebulae, it must travel for 300 times that period, 
or nearly 5,000,000 years ! It is in the contemplation 
of such facts as these that we fully realize our own in- 
significance in the scheme of creation, and feel prepared 
to exclaim, with the Psalmist : " When I consider Thy 
heavens, the work of Thy fingers, the moon and the 
stars which Thou hast ordained, what is man that Thou 
art mindful of him ? and the son of man that Thou vis- 
itest him?" 

Concluding Remarks.— "The Yeil Lifted. 59 

In concluding my lecture, would it not be well to lift 
the veil which shrouds us from futurity ? With boldness, 
yet with humility and reverence, let us proceed to do so. 



A LECTURE ON THE SCIENCE. •>.> 

Who can tell what glorious discoveries will have been 
made in astronomical science after another period of six 
thousand years has rolled slowly away? Looking into 
the distant future, through the dim vista of years, we 
can, in imagination, picture to ourselves the patient as- 
tronomer, still at his task, watching and waiting, and 
grappling with the grand problems of the skies. We are 
apt to dismiss reflections of this nature, thinking that 
but very little remains for the astronomer to accomplish. 
But there are yet "more worlds to conquer." Even 
now hundreds of grand problems are presented to as- 
tronomers for solution which escape their notice ; and 
before another century has rolled away, in thousands of 
lofty observatories, with their gigantic telescopes peering 
heavenward, there may yet be made some of the most 
brilliant discoveries ever chronicled in the annals of as- 
tronomical science. The watch-towers of the heavens 
now cover the whole earth, and the sentinels never 
sleep. Paradoxical as it may seem to you, no star, or 
cluster, or constellation can ever set. It escapes the 
scrutinizing gaze of one astronomer, only to meet the 
equally piercing glance of another. Hark ! from out 
the distant star-depths, and the highways of the plan- 
ets, eastward, westward, northward, southward, peals 
the solemn mandate, "Onward!" This is now the 
watchword of the astronomer; and although the key 
which unlocks the hidden mysteries of the universe still 
remains far beyond our reach, yet, while the amazing 
star-depths lie before us, with their wonders and per- 
plexities — unfathomecl and unfathomable — the true as- 
tronomer will never cease his efforts to interpret rightly 
the grand lessons which they are meant to teach us, 



56 STUDIES IN ASTRONOMY. 

until that time shall come, in the far-distant future, 

when "KNOWLEDGE SHALL BE PERFECTED, AND SOV- 
EREIGN POWER TRIUMPHANT." 



cejaPMjaE]\i>TO¥ ie^imoniW- 

" Mr. Bartlett began the study of astronomy when thirteen years old, and 
has sought a knowledge of the heavens under all manner of discouragements. 
The success he has achieved, and the position he occupies among astronomers, 
warrants the belief that his lecture will be an entertaining one, and Mr. Bart- 
lett a lecturer whom lyceum committees, in search of attractive novelties, would 
do well to negotiate with." — Detroit Free Press. 

"There was an audience fair in numbers and intelligent in character to 
hear Mr. Bartlett's lecture on Astronomy, last evening. The lecture was pre- 
sented in a popular and attractive form, and listened to with absorbing inter- 
est, notwithstanding its great length. Mr. Bartlett is an enthusiastic student of 
science, and he has given to the composition of his subject the best energies of 
his mind, and has adorned it with the brilliant colors of a fine poetical fancy." — 
Battle Creek Journal. 

" Continue on in your chosen pursuit, and as marching years shall come 
and go, you will certainly achieve a distinction which neither you nor your 
friends can now foresee. I have criticised your lecture as you desired, but find 
no errors or fault with it." 

Prof. Lewis Swift, Astronomer, Rochester, N. Y. 

" I read your lecture with great interest, and thought the subject well 
treated. I noticed nothing to criticise." 

Prof. S. W. Burnham, Astronomer, Chicago, 111. 

" It is certainly a most interesting and entertaining review of the advances 
of Astronomy." — Science Observer. 

u The lecture is very well written, and does you credit, both as a student, 
and as evincing fine powers of composition." 

C. M. Davison, Cashier Sec, Nat. Bank, Detroit, Mich. 



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